Global Volcanism Program | Image GVP-03151
The Big Obsidian Flow lava flow in the foreground covers about 2.6 km2 of the floor of Newberry caldera and was emplaced about 1,300 years ago. The eruption occurred at a vent at the base of the southern caldera wall, out of view to the right.
Photo by Lee Siebert, 1984 (Smithsonian Institution).
This image is made available under the Public Domain Dedication CC0 license, but proper attribution is appreciated.